[wasm] Lazy compilation for asm.js

src/wasm/wasm-module.h

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_WASM_MODULE_H_
 #define V8_WASM_MODULE_H_
 
 #include <memory>
 
 #include "src/api.h"
@@ skipping 253 matching lines @@
   int length() const { return module_bytes_.length(); }
 
  private:
   const Vector<const byte> module_bytes_;
 };
 
 // Interface provided to the decoder/graph builder which contains only
 // minimal information about the globals, functions, and function tables.
 struct V8_EXPORT_PRIVATE ModuleEnv {
   ModuleEnv(const WasmModule* module, WasmInstance* instance)
-      : module(module), instance(instance) {}
+      : module(module), instance(instance) {
+    if (instance) {
+      function_tables = &instance->function_tables;
+      signature_tables = &instance->signature_tables;
+    }
+  }
 
   const WasmModule* module;
   WasmInstance* instance;
 
+  // TODO(clemensh): Find a better solution for this.
+  std::vector<Handle<FixedArray>>* function_tables = nullptr;
+  std::vector<Handle<FixedArray>>* signature_tables = nullptr;
+  bool used_indirect_tables = false;
+
+  Handle<FixedArray> GetFunctionTableObj(size_t index) {
+    used_indirect_tables = true;
+    return (*function_tables)[index];
+  }
+  Handle<FixedArray> GetSignatureTableObj(size_t index) {
+    used_indirect_tables = true;
+    return (*signature_tables)[index];
+  }
+
   bool IsValidGlobal(uint32_t index) const {
     return module && index < module->globals.size();
   }
   bool IsValidFunction(uint32_t index) const {
     return module && index < module->functions.size();
   }
   bool IsValidSignature(uint32_t index) const {
     return module && index < module->signatures.size();
   }
   bool IsValidTable(uint32_t index) const {
@@ skipping 147 matching lines @@
 
 V8_EXPORT_PRIVATE void AsyncInstantiate(Isolate* isolate,
                                         Handle<JSPromise> promise,
                                         Handle<WasmModuleObject> module_object,
                                         MaybeHandle<JSReceiver> imports);
 
 V8_EXPORT_PRIVATE void AsyncCompileAndInstantiate(
     Isolate* isolate, Handle<JSPromise> promise, const ModuleWireBytes& bytes,
     MaybeHandle<JSReceiver> imports);
 
+Handle<Code> CompileLazy(Isolate* isolate);
+
 namespace testing {
 void ValidateInstancesChain(Isolate* isolate,
                             Handle<WasmModuleObject> module_obj,
                             int instance_count);
 void ValidateModuleState(Isolate* isolate, Handle<WasmModuleObject> module_obj);
 void ValidateOrphanedInstance(Isolate* isolate,
                               Handle<WasmInstanceObject> instance);
 }  // namespace testing
 }  // namespace wasm
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_WASM_MODULE_H_